(12 Sep 2013, 7:34 pm)aureolin wrote Washington is ran by Sunderland City Council, in a Newcastle postcode area, yet the 'city line' of your address is officially County Durham.
East Durham villages south of Peterlee(Wingate, Trimdon, Castle Eden, Station Town, Blackhall etc) have Teesside Postcodes, a Hartlepool Dial Code despite being Co. Durham